1. Field of the Invention
This invention relates to a parapulper restorative pin for use in dentistry comprising a stem, an end of which is threaded and which is provided with a weakened breaking zone.
This invention relates also to a driving member for such a pin provided with a handle ensuring the connection between it and a motor driving device.
Further, this invention relates also to an assembly constituted on the one hand with a restorative pin for use in dentistry comprising a stem one end of which is threaded and which is provided with a weakened breaking zone and which carries, at its opposite end, a handle permitting to operate it manually, and on the other hand with a driving member ensuring the connection between the said restorative pin and a motor driving device.
2. Description of the Prior Art
Contrarily to that generally designated by the names of "pins" or "root-posts", the parapulper restorative pins are not mounted in the root canal but in the dentine or in the periphery of the root canal. Thus, they can be used even in teeth which have not been previously devitalized.
The parapulper restorative pins for use in dentistry serve to the mounting and for the reinforcement of obturations of recesses in natural teeth or for the armature of reconstitutions of dental crowns which are impaired. (One understands by "obturation" not the operation of obturating but the material of obturation occupying the cavity). These restorative pins are constituted by a threaded stem which is screwed into the root, which has been previously prepared to this effect, and which shows a weakened breaking zone permitting the dentist to break the stem at the desired length, the portion going beyond the root serving to the anchoring and for reinforcement of the obturation or as an armature of the reconstitution of a stump of crown.
The screwing of these pins in the dentine is effected either by hand, in which case the rear end of the stem is provided with a handle that is gripped by the dentist between his fingers for rotating it, or mechanically, in which case the rear end of the stem is provided with means serving as a hold to a driving member which is secured to the handpiece of the dentist.